Ball roller bearings are rolling bearings with special rolling bodies designed as ball rollers, which ball rollers, proceeding from a spherical basic shape, have in each case two side surfaces which are flattened from said spherical basic shape and which are arranged parallel to one another and between which in each case the running surfaces of the ball rollers are arranged. A ball roller bearing of said type is known for example from the German patent application with the file reference 10 2007 062 319.6 which was not published before the filing date of the present patent application, said ball roller bearing being composed substantially of an outer bearing ring and an inner bearing ring and of a multiplicity of ball rollers which are arranged between said bearing rings and which are held with uniform spacings to one another in the circumferential direction by a bearing cage. Here, the ball rollers have a width between their side surfaces of approximately 70% of the diameter of their spherical basic shape, and roll with their running surfaces in two channel-shaped raceways formed into the inner side of the outer bearing ring and into the outer side of the inner bearing ring, the depth of which channel-shaped raceways amounts to approximately 20% of the diameter of the spherical basic shape of the ball rollers. Since the spacing between the inner side of the outer bearing ring and the outer side of the inner bearing ring therefore amounts to only approximately 60% of the diameter of the spherical basic shape of the ball rollers, and the ball rollers can therefore no longer be inserted, as is conventional, axially straight through the spacing between the bearing rings into the ball roller bearing, said ball roller bearing is filled by means of a novel axial-tilt eccentric assembly process in which the inner bearing ring of the two bearing rings, which are arranged in a horizontal concentric position with respect to one another, is initially firstly radially movable slightly along a bearing longitudinal central axis and secondly arranged on an axially offset higher plane than the outer bearing ring, in order to create between the bearing rings a spacing which is larger than the width of the ball rollers. Here, the travel of the radial mobility of the inner bearing ring on the bearing longitudinal central axis, and the height of the axial offset of the two bearing rings with respect to one another, amounts in each case to approximately 25% of the width of the raceways of the bearing rings of the ball roller bearing, since it is thereby ensured that, from the filling of the first ball roller until the filling of the last ball roller, the spacing between the bearing rings is always greater than the width of the ball rollers.
The actual assembly of the ball rollers begins initially in that a first ball roller which is aligned with its side surfaces toward the bearing rings is supplied to the ball roller bearing at the point, provided as a filling point, of the greatest spacing between the bearing rings on the bearing longitudinal central axis, and the inner bearing ring is pushed radially into an eccentric stop position. The ball rollers are thereafter successively inserted, in a slightly tilted position in relation to the outer bearing ring, into the filling point between the bearing rings until the remaining free filling space between the bearing rings corresponds approximately only to the diameter of the spherical basic shape of a single ball roller. After all of the provided ball rollers have been filled into the ball roller bearing, the inner bearing ring is axially lowered while the outer bearing ring is simultaneously axially raised, such that the two bearing rings are arranged in a common plane and the ball rollers which have been tilted into the raceways of the bearing rings are braced between the raceways. In said position, the outer bearing ring is subsequently rotationally accelerated to a rotational speed at which the ball rollers, as a result of intrinsic rotation and as a result of centrifugal force, are automatically aligned and assume a uniformly oblique position within the raceways of the bearing rings. The inner bearing ring and the outer bearing ring are thereafter simultaneously axially lowered until the ball rollers are arranged in a horizontal straight position in the raceways of the bearing rings, and the ball rollers which have been filled in are distributed uniformly on the pitch circle of the ball roller bearing and the bearing cage is inserted through the spacing between the bearing rings.
Although a ball roller bearing of said type is characterized by a high filling ratio with rolling bodies, and therefore a significantly increased radial load-bearing capacity, in relation to a deep-groove ball bearing of the same design, said ball roller bearing simultaneously has the disadvantage that the capability thereof to be loaded with axial forces is subjected to quite narrow limits and it is therefore unsuitable for applications with high tilting resistance and high combined radial and axial forces.
A generic ball roller bearing which is suitable for such applications with high tilting resistance and combined radial and axial forces is, in contrast, already known from DE 100 27 105 A1. Said ball roller bearing is also composed substantially of an outer bearing ring and an inner bearing ring with channel-shaped raceways in each case on the inner and outer sides thereof and also of a multiplicity of ball rollers which roll between said bearing rings in the raceways and which are held with uniform spacings to one another in the circumferential direction by a bearing cage, which ball rollers have between their side surfaces a width which is greater than the radial spacing between the inner side and the outer side of the bearing rings. Here, to permit assembly of the bearing, either the inner or the outer bearing ring is composed of two axially separate ring parts which are connected to one another by means of a screw connection only after the bearing cage has been inserted and filled with the ball rollers. The raceways in the two bearing rings are furthermore divided into in each case two raceway segments by in each case one axially centrally encircling groove, such that in each case two ball rollers which are adjacent to one another are arranged with alternately crossing contact angle axes between the bearing rings in such a way that a first ball roller rolls with its running surface on two first diagonally opposite raceway segments and a second ball roller rolls with its running surface on two second diagonally opposite raceway segments of the inner and outer bearing rings.
A ball roller bearing of said type has however proven to be disadvantageous from numerous aspects, in particular on account of the two-part design of one of the two bearing rings. The two-part design of one of the bearing rings requires increased production and assembly expenditure not only as a result of the increased number of components but also as a result of the need for highly precise production of the tolerance-afflicted parting point between the two ring parts, which increased production and assembly expenditure has an adverse effect on the production costs of a ball roller bearing of said type. Furthermore, the two-part design of one of the bearing rings has the effect that, despite cumbersome bracing of the two bearing rings during bearing operation as a result of arising settling effects, loosening of the assembly can occur, as a result of which the tilting play of the ball rollers is disadvantageously increased, resulting in premature wear of the ball roller bearing. It is likewise disadvantageous that a transportable structural unit cannot be formed with split bearing rings. Finally, the single-piece design of the bearing cage as a window-type cage in such ball roller bearings has proven to be disadvantageous because, in certain load states of the bearing, different relative rotational speeds can arise between the ball rollers inclined with their contact angle axes inclined in one direction and the ball rollers inclined with their contact angle axes in the other direction, as a result of which bracing effects can arise in the bearing cage and increased friction can occur between the ball rollers and their cage pockets in the bearing cage, and which likewise contribute to premature wear of the ball roller bearing.